Intro to Data Analysis

Introduction to Data Analysis

  • UNIT OF ANALYSIS
  • POPULATION
  • SAMPLE
  • N & n
  • DESCRIPTIVE STATISTICS
  • INFERENTIAL STATISTICS
  • TIDY DATA
  • VARIABLES
  • NOMINAL
  • ORDINAL
  • INTERVAL-RATIO
  • DICHOTOMOUS

Unit of Analysis

Who or what is being studied?


POPULATION

All units of analysis (people, institutions, groups, etc.) in which the researcher is interested.


SAMPLE

A subset of people (or institutions, groups, etc.) selected from a population.

DESCRIPTIVE STATISTICS

Procedures that help us organize and describe data collected from a sample or population.


INFERENTIAL STATISTICS

Making underlying predictions or inferences about a population using observations and analyses from a sample.

Tidy Data

VARIABLES

Any factor, trait, or condition that can exist in differing amounts or types.

Measurement Levels

Nominal
A variable made up of categories that cannot be ordered

Ordinal
A variable made up of ranked categories, with no systematic or measurable numeric difference between the categories.

Interval-ratio (aka continuous)
A variable with categories that are ordered and expressed in the same units.

Dichotomous (aka binary)
A variable with only two categories.

Frequency Distributions

  • FREQUENCY DISTRIBUTION
  • RELATIVE FREQUENCY DISTRIBUTION
  • PROPORTION
  • PERCENTAGE
  • CUMULATIVE
  • RATE
  • BAR GRAPH
  • HISTOGRAM
  • LINE GRAPH
  • STATISTICAL MAP

DISTRIBUTION

Shows all the possible values (or intervals) of the data and how often they occur.


FREQUENCY DISTRIBUTION

A table reporting the number of observations falling into each category of the variable.

Table 1. Attitudes about sex before marriage

premarsx

n

not wrong at all

1,378

always wrong

357

wrong only sometimes

258

almost always wrong

122

Total

2,115

premarsx

n

not wrong at all

1,378

always wrong

357

wrong only sometimes

258

almost always wrong

122

Total

2,115

The number of respondents who answered this survey question.

premarsx

n

not wrong at all

1,378

always wrong

357

wrong only sometimes

258

almost always wrong

122

Total

2,115

The number of respondents who said pre-marital sex was “wrong only sometimes.”

Are women more likely than men to say premarital sex is “not wrong at all?”


Table 2. Attitudes about sex before marriage by gender

premarsx

female

male

not wrong at all

11,086

10,672

always wrong

7,116

4,159

wrong only sometimes

4,792

3,904

almost always wrong

2,388

1,499

Total

25,382

20,234

Lab 01

  • CODEBOOK

will add later